1) What is an Actuator? Give an Example.

 An actuator is a device that converts energy (electrical, hydraulic, or pneumatic) into

motion.

 It is commonly used in machines, robots, and automated systems.

 Example: A robotic arm in a factory uses an actuator to move and lift objects.

2) What Are the Two Types of Projectors?

The two main types of projectors are:

1. DLP (Digital Light Processing) Projector

2. LCD (Liquid Crystal Display) Projector

(You need to draw diagrams of both projectors. Let me know if you need help with a
description for the drawing.)

3) Advantages and Disadvantages of DLP and LCD Projectors

Feature DLP Projector LCD Projector

Advantages - Higher contrast and sharper images - Better color accuracy and brightness

- Faster response time - Energy-efficient

Disadvantages - Rainbow effect in fast-moving scenes - Can develop dead pixels over time

- More expensive - Slightly lower contrast ratio

4) Two Technologies of Inkjet Printers

Inkjet printers use two main technologies:

1. Thermal Bubble (Bubble Jet)

o Tiny resistors heat the ink, creating a bubble that expands and forces ink onto
the paper.

2. Piezoelectric Technology

o A vibrating crystal pushes ink droplets onto the paper without using heat.

5) Steps in the Inkjet Printing Process

 1. Data Processing: The printer receives and analyzes the document.

2. Ink Droplet Formation: Ink is heated (thermal) or vibrated (piezoelectric) to form

droplets.

3. Droplet Ejection: The printhead sprays tiny ink droplets onto the paper.

4. Paper Movement: The paper moves forward step by step as printing continues.

5. Ink Drying: The ink dries quickly to prevent smudging.

6) Steps in the Laser Printing Process

1. Data Processing: The printer processes the document.

2. Charging: A laser beam creates an electrostatic image on the drum.

3. Toner Application: Toner powder sticks to the charged areas.

4. Transfer: The toner is transferred to the paper.

5. Fusing: The paper passes through heated rollers to fix the toner permanently.

7) Applications of Inkjet, Laser, and 3D Printers

 Inkjet Printer: Used for high-quality color images and documents at homes and
offices.

 Laser Printer: Preferred for fast, high-volume printing in businesses and schools.

 3D Printer: Used for creating models, prototypes, medical implants, and customized
objects.

8) Materials Used in 3D Printing

 Plastics (PLA, ABS, PETG) – Common for prototypes and household objects.

 Metals (Titanium, Aluminum, Stainless Steel) – Used in industrial and medical

applications.

 Ceramics and Resins – Used in art and dental industries.

 Food Materials (Chocolate, Sugar, Dough) – Used in food printing.

9) What is Binder 3D Printing and Direct 3D Printing?

 1. Binder 3D Printing: Uses a liquid binder to glue powder-based materials together to
form layers.

2. Direct 3D Printing: Uses melted materials (like plastic or metal) to directly create
solid objects.

10) Uses of 3D Printing

 Manufacturing customized tools and machine parts.

 Creating medical implants and prosthetics.

 Building architectural models and prototypes.

 Printing food, clothing, and even houses.

11) Advantages of LED Over CCFL Technology

 Energy Efficiency: LED uses less power than CCFL.

 Better Brightness & Color: LED displays are brighter with more vivid colors.

 Longer Lifespan: LEDs last longer than CCFL lights.

 Thinner & Lightweight Design: LED screens are slimmer and more portable.

12) Advantages of OLED Compared to LED & LCD

 Better Picture Quality: OLED provides deeper blacks and more vibrant colors.

 Flexible & Thinner Design: OLED screens are thinner and can be flexible.

 Faster Response Time: No motion blur in fast-moving images.

 Power Efficiency: Uses less power when displaying dark images.

13) Diagram of Digital to Analog Conversion

(You need to draw a diagram showing how a digital signal (binary 1s and 0s) is converted
into an analog waveform.)

14) Definitions: Sensor, ADC, DAC

  Sensor: A device that detects physical changes (temperature, light, pressure, etc.)
and converts them into electrical signals.

 ADC (Analog-to-Digital Converter): A device that converts an analog signal

(continuous) into a digital signal (binary format).

 DAC (Digital-to-Analog Converter): A device that converts digital signals (binary) into
analog signals (continuous waveforms).

15) Description of Sensors and Their Applications

Sensor Type Description Application

Temperature Measures temperature changes Used in air conditioners, refrigerators,

Sensor in the environment. and weather stations.

Detects water or moisture levels Used in agriculture and irrigation

Moisture Sensor
in soil or materials. systems.

Measures the amount of water Used in HVAC systems and weather

Humidity Sensor
vapor in the air. forecasting.

Detects the intensity of light in Used in automatic street lighting and

Light Sensor
the surroundings. smartphone brightness adjustment.

Detects infrared radiation Used in remote controls, security

Infrared Sensor
emitted by objects. systems, and motion detectors.

Measures pressure changes in air Used in automotive tire pressure

Pressure Sensor
or liquids. monitoring and weather stations.

Measures the acidity or alkalinity Used in water quality testing and

pH Sensor
of a liquid. chemical industries.

Proximity Detects the presence of objects Used in automatic doors, mobile

Sensor without physical contact. phones, and industrial robots.

16) Diagram of a Monitoring & Control System Using Sensors

(You need to draw a diagram showing how sensors collect data, send it to a processor, and
trigger a response in a control system.)

17) Examples of Monitoring and Control Systems

 1. Smart Street Lighting: Automatically turns on/off based on surrounding light
conditions.

2. Home Security System: Uses motion detectors and cameras to detect intruders.

3. Automated Greenhouse: Uses temperature and moisture sensors to control

irrigation and ventilation.

18) Diagram of a Security System (Monitoring System)

(You need to draw a figure showing how a security system works, including motion sensors,
cameras, alarms, and control units.)

19) Diagram of a Control System (Street Lighting)

(You need to draw a diagram showing how a light sensor controls streetlights, turning them
on at night and off during the day.)

Data Storage

1) Two Differences Between Primary and Secondary Storage

Primary Storage Secondary Storage

Faster and directly accessible by the CPU. Slower and requires retrieval before CPU access.

Temporary storage (RAM, Cache). Permanent storage (HDD, SSD, USB).

Has limited capacity (measured in GB). Has larger capacity (measured in TB).

2) Features of RAM and ROM

RAM (Random Access Memory) ROM (Read-Only Memory)

Non-volatile (data remains even after power

Volatile (data is lost when power is off).
loss).

Used for temporary storage of running

Stores firmware and system boot information.
programs.

Faster but expensive. Slower but cheaper.

3) Advantages of DRAM Over SRAM

DRAM (Dynamic RAM) SRAM (Static RAM)

Cheaper and has higher storage capacity. Faster but more expensive.

Needs constant refreshing. Does not require refreshing.

Used in main memory (RAM). Used in cache memory (CPU cache).